Valve construction



June 13, 195? D. (5. WAY

VALVE CONSTRUCTION 2 Sheet-Sheet 1 Filed Jan. 2, 1964 June 13, W6? D. c-a. WAY

VALVE CONSTRUCTION 2 Sheets-.Sheet 2 Filed Jan. 2, 1964 United States Patent 3,324,886 VALVE CONSTRUCTION David G. Way, Boxborough, Mass. (West Acton, Mass. 01780) Filed Jan. 2, 1964, Ser. No. 335,045 9 Claims. (Cl. 137625.48)

This invention relates to a valve assembly of improved construction and pertains more specifically to a valve assembly having two or more ports and having a valve member movable to to and from first and second positions for interconnecting various combinations of ports.

The valve members in such valves are conventionally moved from one position to the other by actuators located adjacent opposite ends of the valve and operated by a suitable signal. Such actuators have been driven by solenoids, by fluid pressure, or by cams but in each case it has been necessary to cancel the signal applied to one actuator before a signal could be applied to the other actuator in order to return the valve member to its original position. In some applications however, it has been diflicult or impossible to provide for cancellation of one signal before the other is applied.

One object of the present invention is to provide a valve assembly of the type described in which the actuator when it has reached its driven position after driving the valve member leaves the latter free to be returned to its original position without the necessity for returning the actuator to its home position.

Other and further objects will be apparent from the drawings and from the description which follows.

In the drawings FIG. 1 is a view in section showing one embodiment of the present invention;

FIG. 2 is a view in section taken along line 22 of FIG. 1;

FIG. 3 is a view in section showing a second embodiment of the invention;

FIG. 4 is a view in section taken along line 4-4 of FIG. 3;

FIG. 5 is a view in section showing a third embodiment;

FIG. 6 is a view in section taken along line 66 of FIG. 5;

FIG. 7 is a view partly broken away and in section showing a fourth embodiment; and

FIG. 8 is a view in section taken along line 8-8 of FIG. 7.

As shown in FIGS. 1 and 2 of the drawing the threeway valve embodiment illustrated includes a valve housing 19 in the form of a cylinder within which is mounted valve member or spool 12 for reciprocating movement within the cylinder. A spring-loaded detent 14 is provided in the inner wall of cylinder in position to engage a circumferential groove 16 in spool 12. A second circumferential groove 18 is provided in the spool spaced from groove 16 and a second position in which the detent is from a first position in which detent 14 is engaged in firoove 16 and a second position in which the detent is engaged in groove 18. A pair of ports 20, 22 communicate with one side of the valve at positions axially spaced from each other and a third port 24 communicates with cylinder 10 at a position intermediate of the first two ports. A central portion 26 of valve member 12 is of reduced diameter while the end portions are in sealing engagement with the wall of cylinder 10 so that the valve element acts as a piston and so that port 24 is in communication with port 20 when the valve member is in its first position, while port 24 is in communication with port 22 when the valve member is in its second position.

Mounted adjacent each end of valve cylinder 10 are actuator cylinders 30, 32, one end of each cylinder being in communication with the adjacent end of valve cylinder 10 through ports 34, 36. Within each actuator cylinder is an actuator in the form of piston 38, 40 mounted for reciprocating movement in sealing engagement of the wall thereof. Inlets 42, 44 are provided for introducing pressure fluid into the respective actuator cylinders to move the actuators from their home or lower positions as seen in FIG. 1 to their upper or driven positions. Compression springs 46, 48 are provided to return the actuators from their driven positions to their home positions when the fluid pressure is released. Exhaust ports 59, 52 are provided in the walls of the actuator-cylinders and the central portion of each actuator piston 38, 40 is of reduced diameter to permit direct communication between ports 34, 36 and exhaust ports 50, 52 when the actuator pistons are in their driven posit-ions, thus permitting the respective ends of valve cylinder 10 to be exhausted. Spring-loaded check valves 54, 56 are provided in the ends of actuator-cylinders 3t), 32 to permit return movement of each actuator piston from its driven position to its home position without changing the fluid pressure in the adjacent end of valve cylinder 10.

In operation of this embodiment a suitable signal is provided to supply fluid pressure, either pneumatic or hydraulic, through port 44 to actuator cylinder 32. As actuator piston 40 is urged forward from its home position to its driven position by this fluid pressure, it first seals off exhaust port 52, after which the fluid trapped between the upper end of piston 40 and the adjacent end of valve member 12 is compressed, urging the valve ele ment to the first position as shown in FIG. 1. When actuator piston 40 reaches its driven position as shown in FIG. 1 any residual pressure in the adjacent end of valve cylinder 10 is vented through ports 36 and 52.

If before the first signal is cancelled a second signal is applied to supply pressure fluid through port 42, actuator piston 38 advances in the same manner as did actuator piston 40 and urges valve member 12 to its second position by forcing trapped fluid through port 34 against the adjacent end of valve member 12 while the fluid at the opposite end of the valve member is exhausted through ports 36 and 52 without moving actuator piston 40.

Whenever either signal is cancelled and the fluid pressure is withdrawn from ports 42 or 44, the respective actuator piston is returned to its home position by means of spring 46 or 48, the respective check valves 54, 56 serving to prevent any pressure drop in the actuatorcylinder which might cause displacement of valve element 12.

In the embodiment of the invention shown in FIGS. 3 and 4 the invention is applied to an internally pressurized four-way valve in which the valve housing or cylinder 60 is provided with three ports 62, 64, 66, port 66 being the inlet port for pressurized fluid, and in addition is provided with exhaust ports 68. Valve member or spool 70 is provided with two zones of reduced diameter 72, 74 and with an intermediate portion 76 which is in sealing engagement with the wall of cylinder 60 as are the two end portions, so that the valve member functions as a piston in cylinder 60. The two actuatorcylinders 78, 79 are mounted at opposite ends of valve cylinder 60 and communicate therewith through ports 80, 81 In this embodiment, however, ports 82, 83, instead of being vented directly to the atmosphere are connected by means of passageways 84, 85 with inlet port 66. Check valves 86, 87 likewise are mounted at the ends of cylinders 78, 79 to communicate with passageways 84, 85 rather than with the atmosphere. Actuator pistons '88, 89 in this case have much larger diameters at their lower ends than at their upper; cylinders 78, 79 are provided with the correspondingly enlarged diameters at their lower ends and with ports 90, 91. Two spring-loaded detents 92, 94 are mounted in the wall of cylinder 60 in position to engage groove 96 in the periphery of valve member 70 so that the valve member may be releasably held in either first or second position.

The operation of this embodiment is analogous to that of the embodiment shown in FIGS. 1 and 2 except that the pressure of the fluid supply rather than that of the atmosphere is used as the base pressure, thus making possible a greater driving force for shifting the valve member and eliminating the need for return springs, the pressure applied from inlet 66 through check valves 86, 87 serving to return pistons 88, 89 by overbalancing the pressure on the underside of the relatively narrow overhanging marginal portions at the top of each piston when the pressure is released from port 90 or 91. Reciprocation of valve member 70 from one position to another within cylinder 60 places port 62 in communication either with the exhaust port 68 or with pressure fluid supply port 66, and also places port 64 in communication either with exhaust 68 or with supply port 66. When both actuator pistons 88, 89 are in their home or lower positions, the upper portions of both actuator cylinders as well as the adjacent ends of valve cylinder 60 are in communication with port 66 and are maintained at the same pressure as the supply. A suitable conventional signal mechanism causes the application of pressure fluid to port 91. Because of the larger diameter of the lower portion of cylinder 79, fluid at the same pressure as in supply port 66 may be used and will drive actuator piston 89 upwardly to its driven position, trapping and compressing the fluid ahead of it in the actuator cylinder and urging valve member 70 to the left to the position shown in FIGS. 3 and 4. When actuator 89 reaches its driven position, any excess pressure remaining in cylinder 60 is vented through port 81, around the center portion of actuator 89 and through port 83 and passage 85 to the supply port 66. The remainder of the operation is analogous to that of the embodiment of FIGS. 1 and 2.

In the embodiment shown in FIGS. 5 and 6 valve cylinder 100 and valve member 102 are similar to those shown in FIGS. 1 and 2, being provided with three ports 104, 106, 108 which are arranged for alternative connection with each other by shifting of the valve member 102 from one position to another. In this embodiment rotary cams 110, 112 are provided to actuate the valve member, each being mounted for rotation on a drive shaft 114, 116. Each actuator 110, 112 is provided with four lobes tor cam portions 118, 118 while shafts 114, 116 are provided with a suitable means (not shown) for rotating each of them thru an arc of 90 upon signal. The drive 'shafts may be actuated by rotary solenoids, over-running clutches, or other conventional mechanisms.

As will be apparent from inspection of FIG. 5, actuator 110 is shown in position to drive valve member 102 to the right by clockwise rotation of drive shaft 114 thru 90. The opposite end of the valve member is unobstructed by cam 112 and the member is free to move to its second position even though the signal which actuated cam 112 has not been cancelled. Similarly a new signal may subsequently be given to cam 112 without cancellation of signal of cam 110' and will be effective to return the valve member to its original position.

In the embodiment shown in FIGS. 7 and 8 valve cylinder 120 and valve member 122 are again similar in construction and operation to those shown in FIGS. 1 and 2. In this embodiment, however, actuators 124, 126 are mounted for reciprocating movement in guideways 128, 129 at opposite ends of valve cylinder 120, being retained in position by pins 140, 141 fixed to the respective actuators and riding in retainer slots 142, 143 in the wall of the respective guideway. Projecting laterally from each actuator 124, 126 is a cam portion 130, 131 urged by a compression spring 132, 134 into position for positive engagement with an end of the valve member when the actuator is driven from its home position to driven position and arranged to be yieldably retracted to clear the end of the valve member during return movement of the actuator to its home position. Compression springs 136, 138 are provided for returning each actuator to its home position. The mechanism for driving each actuator may be any conventional mechanism such as a cam, solenoid, etc.

In operation of this embodiment actuator 126 is driven from its home position, cam portion 131 engaging the end of valve member 122 and urging the member to the right as the actuator is advanced in its driving movement. When the actuator has reached its driven position as shown in FIG. 7 the cam portion 131 has cleared the end of the valve member leaving it free to be returned to its original position even though the signal actuating the mechanism driving the actuator 126 has not been cancelled. The actuators are returned to home position by their respective compression springs 136, 138 regardless of the position of valve member 122 as soon as respective signals have been cancelled. If the end of the valve member is engaged by the cam portion during the return movement of the actuator, cam portion 130 or 131 as the case may be is retracted into the body of actuator 124 or 126 by compression of spring 132 or 134 permitting the cam portion to clear the end of the valve member. As soon as the actuator reaches its home position, as shown for actuator 124 in FIG. 7, the cam portion is again advanced into position for positive engagement with the valve member during driving movement of the actuator.

Although specific embodiments of the invention have been herein described it is not intended to limit the invention solely thereto but to include all of the obvious variations and modifications within the spirit and scope of the appended claims.

What is claimed is:

1. A valve assembly containing a valve member movable to and from first and second positions in combination with an actuator for driving said valve member from first to second position, said actuator being mounted for reciprocating driving movement from a home position to a driven position, said actuator including means whereby when said actuator is in said driven position said valve member is free to be returned to said first position without further movement of said actuator, means being provided for returning said actuator to home position.

2. A valve assembly as claimed in claim 1 in which the last said means comprises a spring.

3. A valve assembly containing a valve member movable to and from first and second positions in combination with a first acturator for driving said valve member from first to second position and a second actuator for driving said valve member from second to first position, each said actuator being mounted for independent driving movement from a home position to a driven position, each said actuator including means whereby when said actuator is in said driven position said valve member is free to be returned by said other actuator without further movement of said actuator in said driven position.

4. A valve assembly as claimed in claim 3 in which each said actuator and said valve member comprises a piston mounted for reciprocation within a cylinder whereby driving movement of each said actuator drives said valve element by fluid pressure.

5. A valve assembly as claimed in claim 3 in which each said actuator includes a cam portion mounted for driving contact with said valve element.

6. A valve assembly as claimed in claim 5 in which each said actuator is mounted for rotary movement.

7. A valve assembly as claimed in claim 3 in which each actuator is mounted for reciprocating movement and includes a cam portion mounted for driving contact with said valve element, means is provided for returning each actuator to home position, and each cam portion is spring-loaded and is mounted on its actuator for positive engagement With said valve member during said driving movement and for yielding retraction to clear said valve member during return movement in the opposite direction.

8. A valve assembly containing a valve member comprising a piston mounted for movement to and from first and second positions Within a valvecylinder, an actuatorcylinder having one end in communication with one end of said valve cylinder, an actuator comprising a piston mounted for driving movement in said actuator-cylinder from a home position to a driven position adjacent said one end for driving said valve member by fluid pressure from first to second position, and means for venting said one end of said valve cylinder when said actuator reaches said driven position to permit said valve member to be returned to first position while said actuator remains in its driven position.

9. A valve assembly as claimed in claim 8 in Which said valve member comprises a double-ended piston, and

including a second actuator cylinder having one end in communication with the other end of said valve cylinder, at second actuator comprising a piston mounted for driving movement in said second actuator cylinder from a home position to a driven position adjacent said one end for driving said valve member by fluid pressure from second position to first position, and means for venting said other end of said valve cylinder when said second actuator reaches its driven position to permit said valve member to be returned to second position While said actuator remains in its driven position.

References Cited UNITED STATES PATENTS 139,227 5/1873 Ames 7455 2,452,295 10/1948 Elliott 251-251 X 2,806,431 9/1957 Woydt 7444- X 2,816,420 12/1957 Walsh l37----625.66 X

M. CARY NELSON, Primary Examiner.

HENRY T. KLINKSIEK, Examiner.

UNITED STATES PATENT OFFICE CERTIFICATE OF CORRECTION Patent No 3 ,324 ,886 June 13 1967 David G. Way

It is hereby certified that error appears in the above numbered patent requiring correction and that the said Letters Patent should read as corrected below Column 1, line 11, strike out "to", second occurrence; line 56, strike out "and a second position in which the detent is" and insert instead Valve member 12 is mounted for movement line 58, for "firoove" read groove column 4, line 54, for "acturator" read actuator Signed and sealed this 18th day of June 1968 (SEAL) Attest:

Edward M. Fletcher, Jr. EDWARD J. BRENNER Attesting Officer Commissioner of Patents 

1. A VALVE ASSEMBLY CONTAINING A VALVE MEMBER MOVABLE TO AND FROM FIRST AND SECOND POSITIONS IN COMBINATION WITH AN ACTUATOR FOR DRIVING SAID VALVE MEMBER FROM FIRST TO SECOND POSITION, SAID ACTUATOR BEING MOUNTED FOR RECIPROCATING DRIVING MOVEMENT FROM A HOME POSITION TO A DRIVEN POSITION, SAID ACTUATOR INCLUDING MEANS WHEREBY WHEN SAID ACTUATOR IS IN SAID DRIVEN POSITION SAID VALVE MEMBER IS FREE TO BE RETURNED TO SAID FIRST POSITION WITHOUT FURTHER MOVEMENT OF SAID ACTUATOR, MEANS BEING PROVIDED FOR RETURNING SAID ACTUATOR TO HOME POSITION. 